Flow regulator



May 3, 1960 R. D. THOMPSON El AL FLOW REGULATOR Filed April 28, 1955 FLOW REGULATOR Robert Donovan Thompson and Raymond W. Barton, Evansville, Ind., assignors, 'bymesne assignments, to 011 gaxter, Inc., Glendale, Califi, a corporation of eva a Application April 28, 1955, Serial No. 504,398

6 Claims. (Cl. 137-613) This invention relates to a flow regulator and in particular to a flow regulating clamp for use with compressible tubing as in parenteral fluid administrating systems.

Systems for administrating parenteral liquids as blood plasma including a source of the liquid, and a conduit for transferring the liquid from the source through suitable means, as a hypodermic needle, into the patient are well known in the art. For use with such systems clamping means are provided which are arranged adjustably to constrict or compress the tubing comprising the conduit to cause a variable fluid flow therethrough. Certain parenteral fluid dispensing systems in the art are provided with simple compressors of a type comprising a flat rigid plate having a slot with portions of varying width through which the tube is passed, and by the positioning of the tube in the portion of the slot having the desired width, desired constriction of the tube is effected. Such compressors have the serious fault of difliculty of accurate regulation and inability positively to retain the tube in the position selected. Further, they have been found to require the use of both hands of the person utilizing them which is often disadvantageous in the administration of the parenteral liquid. Still further, should a complete shut off of the fluid flow momentarily be desired, the original positioning of the tube in the slot is lost and the diflicult adjustment of the positioning of the tube in the slot again is required when the flow is returned to the normal rate.

Other flow control clamps known in the art have serious disadvantages in that they are relatively complicated and costly of manufacture so that reuse requiring maintenance and cleaning is economically necessitated. Such clamps, being ordinarily provided separate from the other dispensing system components, may not be available when desired, the likelihood of such unavailability being increased where field use is involved.

The principal feature of this invention is the provision of a new and improved flow regulator.

' Another feature is the provision of a new and improved flow regulator which is simple and economical of construction so as to be economically disposable while yet providing means for positive regulation of flow in a parenteral liquid dispensing system.

Still another feature of the invention is the provision of a flow regulator comprising a bolt having a diametric slot for freely receiving fluid transmitting tubing, and a nut mounted on the bolt for adjustably compressing and releasing the tubing.

A further feature is the provision of a flow regulator which may be easily grasped and manipulated, one hand only of the user being required for such action.

A still further feature is the provision of a new and improved flow regulator having adjustable flow regulation means and independent, instantaneous, positive flow stoppage means.

Still another feature is the provision of a flow regulates' Patent tor comprising a bolt and a nut for adjustably compressing tubing against the bolt with integral means on the bolt for preventing inadvertent separation of the bolt and nut.

Other features and advantages of this invention will be apparent from the following description taken in connection with the accompanying drawings wherein;

Figure 1 is an elevational view of a parenteral system having a flow regulator embodying the invention;

Figure 2 is an enlarged side elevational view of the flow regulator as installed on a portion of the parenteral liquid dispensing system tubing;

Figure 3 is an elevational view of the flow regulator looking from the right of Fig. 2 and with the tubing positioned in the flow blocking means;

Figure 4 is a vertical sectional view taken approximately along the line 4-4 of Fig. 3;

Figure 5 is an exploded view of the flow regulator partially in section; and

Figure 6 is a front elevational view of the flow regulator bolt member.

In the exemplary embodiment of the invention shown in the drawings, the flow regulator, designated 10, is installedon a portion of a flexible tube 20 which is attached at one end to a source of parenteral liquid 21 through suitable filter means 21a and which is provided at theother end with means 22 for injecting the fluid into a patient (not shown). Tube 20 is formed of a resiliently deformable material as rubber or a plastic which allows control of liquid flow therethrough by compression thereof resulting in a constriction of the internal tube passage. Flow regulator 10 generally comprises a first element or bolt 11 having operating coaction with a second element or nut 15 adjustably to constrict tube 20 for regulation of the flow. Such coaction is effected through the threaded movement of the nut 15 on bolt 11 to allow positive and accurate positioning by manipulation with one hand only of the parenteral fluid administrator.

Referring now more particularly to Figures 2 to 6 0 the drawings, bolt 11 may be seen to comprise a shank 12 having an outer end 12a and an inner end 12b with a diametrical slot extending longitudinally of shank 12 and having an inner end 120 spaced from shank inner end 12b, and an opening 120" in the shank outer end 12a. The width of slot 12c is made somewhat greater than the external diameter of the tube 20 so that it is adapted freely to receive the tube and permit desired flattening of the tube when it is compressed. Extending longitudinally outwardly from shank inner end 12b is a relatively thin wall 12d circumferentially bounding the slot inner end 12c. 'A single wall 12d at one end only of the slot is preferred to permit constriction of the tube 20 at one portion only.

Shank 12 is exteriorly threaded in its portion 12e partially surrounding the slot 120 from a point spaced from bolt outer end 12a and to a point spaced from slot inner end 12c for receiving nut 15. Bolt 11 is preferably formed of a material as a plastic having some resiliency so that the opposed portions of shank outer end 12a may be urged somewhat toward each other allowing the move-' ment of nut 15 over the unthreaded outer end and with nut 15 positioned surrounding the threaded portion 12e, the outer end portions may be released allowing threaded engagement between an internally threaded portion 15a of the nut 15 and bolt threaded portion 12c.

Nut 15 is an annular member preferably formed of moldable plastic and is provided with a thin edged inner end or wall 15b which is adapted to have complementary relationship with shank wall 12d for clamping tube 20- therebetween. We have found that the clamping effect is more readily obtained through the use of the thin edged wall 12d and thin nut end 15b as the friction between the tube and the nut is reduced and the clamping force is localized. A similar but reduced effect is obtained through use of a single such thin element mating with a broad complementary element as where the wall 12d is verybroad or eliminated. An exemplary satisfactory clamp is one wherein the outer diameter of the nut is V2", nut end 15b is Wide and wall 12d is A wide. To facilitate rotation of nut 15 on shank f2, outer periphery 150 of the nut may be knurled or grooved in a suitable manner as shown. To facilitate manufacturing, nut threaded portion 15a in the embodiment shown comprises a single thread extending not more than 360 allowing separation of the forming mold sections.

Extending laterally outwardly from shank inner end 12b is a base 13 comprising a first portion 13a and an oppositely extending second portion 13b. Sufficient lateral extension is provided to allow ready grasping of the regulator for manipulation thereof. First portion 13a is provided with a slot 13c which is tapered inwardly from the outer end 13a to have its smallest cross-section adjacent shank inner end 1%. The taper is made gradual so that tube 20 may be forced into the slot from the outer end 13a, being increasingly constricted the further it is positioned in from the outer end and being completely blocked when positioned at the inner end of the slot.

Regulator may be readily installed, as by the manufacturer of the parenteral system assembly, on the tube 20 by moving the desired portion of the tube laterally into shank slot 120 with nut removed from the bolt 11. Shank outer end 12a is then compressed inwardly somewhat and nut 15, with inner end 15b foremost, moved thereover into threaded engagement with portion 1% of the shank, whereupon outer end 12a is released. Nut 15 may then be rotated to advance axially toward inner end 12b of the shank until nut inner end 15b is urged againstthe tube compressing it against shank wall 12d the desired extent. Further axial movement toward inner end 12b may be had until the tube walls are forced together completely blocking the passage through the tube, and conversely nut 15 may be retracted by reverse rotation thereof to allow tube 20 to be fully expanded and allow maximal flow. Nut 15 will not ordinarily be backed off threaded portion 12e as the unthreaded outer shank portion adjacent end 12a prevents such inadvertent movement. If, however, it is desired to remove nut 15, outer end 12a may be compressed, as in installation, allowing the removal of the nut.

If at any time during the administration of the parenteral liquid, it is desired instantaneously and positively, completely to block the flow of the liquid, the adjacent portion of tube 2-9 may be jerked or quickly placed fully into slot 130 in base 13 while leaving the flow controlling postion of nut 15 unchanged. Considering the nut-bolt structure as a first valve means and the wedge-shaped slot structure as a second valve means, in the operation of the second valve means it is to be noted that the nut is operable to grip the tube and retain it against relative longitudinal movement and a portion of the first valve means opposite the second valve means is arranged for engagement by one of the users fingers while another of the users finger is urging the tube into the wedgeshaped slot of the second valve means to effect a substantially instantaneous termination of the flow. Should a temporary reduction in flow be desired, the adjacent portion of tube 20 may be inserted partially into slot 130 while similarly leaving the positioning of nut 15 unchanged.

As the regulator is preferably formed of moldable plastic, it may be produced in mass quantities efficiently and economically, 'allowing disposing thereof together with the commonly dispesable parenteral elements, as the tube and needle. V V

While we have shown and described certain embodiments of our invention, it is to be understood that it is capable of many modifications. Changes, therefore, in the construction and arrangement may be made without departing from the spirit and scope of the invention as disclosed in the appended claims.

We claim:

1. A flow regulator of; the. character described for use in a parenteral fluid dispensing system to control the flow through a resiliently compressible tube, comprising: a bolt formed of resiliently deformable plastic, having an outer end, a tube receiving diametrical slot opening at the outer end, a thin edge circumferential wall extending laterally across an inner end of said slot and toward said bolt outer end, said bolt being exteriorly threaded from a point spaced from said outer end and a nut threadedly mounted on said bolt and, having a thin circumferential edge directed toward said bolt wall and movable toward said bolt wall when the nut is advanced on the bolt.

2. A flow regulator of the character described for use in a parenteral fluid dispensing system to control the flow through a resiliently compressible tube, comprising: an exteriorly threaded bolt formed of a moldable plastic, having an outer end, a tube receiving diametrical slot opening at the outer end, a thin edged circumferential wall extending laterally across an inner end of said slot and toward said bolt outer end; and a nut threadedly mounted on said boltand having a thin circumferential edge directed toward said bolt wall and movable toward said bolt wall when the nut is advanced on the bolt to a point closely adjacent said bolt wall.

3. A flow regulator of the character described for use in a parenteral fluid dispensing system to control the flow through a resiliently compressible tube, comprising: an exteriorly threaded element having an outer end, a tube receiving diametrical s lotopening at the outer end, a thin-edged circumferential wall extending laterally across an inner end of said slotand projecting a substantial distance toward said element outer end; and a nut threadedly mounted on said element and having a thin circumferential edge aligned with and projecting a substantial distance toward said element wall and movable toward said element wall when the nut is advanced on the element to a point closely adjacent said element wall.

4. Means for controlling parenteral fluid administration comprising a flow regulator arranged for fit in and manipulation by one handof a user to adjust the volume rate of flow as desired and alternatively to effect a substantially instantaneous termination of flow, said regulator including a first valve means having aslot through which a resilient parenteral fluid administration tube may be extended and a manually operable control means for adjustably gripping the tube to retain it against longitudinal movement and constricting the tube in the slot to vary the volume rate of fluid flow therethrough, and a second valve means having a wedge-shaped slot fixedly associated with the first valve means, a portion of the first valve means opposite the second valve means being arranged for engagement by one of the users fingers while another of the users fingers is urging the tube into the wedge-shaped slot of the second valve means to effect a substantially instantaneous termination of flow.

5 The means for controlling parenteral fluid admin- I istration of claim 4 wherein the second valve means extends closely adjacent a plane of the bottom of the slot of the first valve means to permit insertion of the duct into the slot of the second valve means by a small lateral movement of the tube.

6. The means for controlling parenteral fluid administration of claim 4 wherein the second valve means is aligned with the slot of the first. valve meansv and opens away therefrom.

(References on following page) References Cited in the file of this patent UNITED STATES PATENTS Arnstein July 22, 1924 Waltz Nov. 22, 1927 5 Crowley Apr. 24, 1928 Gray Nov. 7, 1944 6 Fields pr. 11, 1950 Woodward July 4, 1950 Siesel Apr. 17, 1951 Hoffman June 30, 1953 Huber Sept. 21, 1954 Davidson Nov. 2, 1954 

